I called the web support line and was able to change my flights. At first I was told 20K extra miles then 90K but I was able to explain how the region of my flights hadn't changed and that the pre-deval 140K was correct for F to S Asia. After about 30 minutes on hold they agreed and made the change after paying change fees.
Original flights:
SFO-NRT (stopover)
HND-HKG (stopover)
HKG-PEK-SFO
Changed to:
SFO-NRT (stopover, OJ)
SIN-HKG (stopover)
HKG-ICN-SFO